Yeah, it's pretty much considered taboo to relate your UTAU to any existing Vocaloid or UTAU characters, without their creator's permission. So it's very unlikely you could get Teto's creator's permission for that ;u;

However, having your UTAU admire an existing UTAU or Vocaloid is fine c: A lot of people do that (for instance, Makune Hachi is based off Macne Nana, but Misha does not claim her to be officially related to the real Macloids, though it's obvious that Hachi's inspired by them and idolizes them~)